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ANALYSIS OF THE ENVIRONMENT FEATURE OF BREEDING AREA AND ENDANGERED FACTORS OF RED-CROWNED CRANE IN CHINA

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Chinese Geographical Science 2001年第2期11卷 186-191页

作者： YU jun-bao, liu Jing-shuang, WANG Jin-da (Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021,P.R.China) Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

Red-crowned Crane (Grus japonensis), a kind of endangered large-scale wader, is one of valuable and rare birds in the world. It has been indexed in China Red Data Book of Endangered Animals (Aves), China Data Book of Major Protection Wild Animals, World Red Data Book of Birds, State Trade Protocol of Endangered Wild Plants and Animals Species. The paper studies the amount, distribution, habit, growth and habitat of Red-crowned Crane in China in detail, systematically analyses the ecological environment feature of Red-crowned Crane breeding area, including the vegetation feature, the vertical distribution law of absolute humidity and temperature, some carnivorous food and herbivorous food for Red-crowned Crane. At present, the ecological environment of breeding area has been destroyed seriously by human activity. The area of marshland is reduced rapidly. A large area of reeds has been disappeared. The survival of Red-crowned Crane is threatened greatly. So it′s necessary to maintain the biodiversity of breeding area in order to protect Red-crowned Crane. .

关键词： Red-crowned Crane nature reserve conservation environment

RNA interference against interleukin-5 attenuates airway inflammation and hyperresponsiveness in an asthma model

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第1期10卷 22-28页

作者： Shao-xing CHEN Feng-ying HUANG Guang-hong TANi Cai-chun WANG Yong-hao HUANG Hua WANG Song-lin ZHOU Fan CHEN Ying-ying LIN jun-bao liu Hainan Provincial Key Laboratory of Tropical Medicine Hainan Medical College Haikou 571101 China Department of Digestive Diseases Affiliated Hospital of ttainan Medical College Haikou 570102 China

Interleukin-5 (IL-5) accompanies the development of airway inflammation and hyperresponsiveness through the activation of eosinophils. Therefore, interference of IL-5 expression in lung tissue seems to be an accepted approach in asthma therapy. In this study, we designed a small interfering RNA (siRNA) to inhibit the expression of IL-5. The siRNAs against IL-5 were constructed in a lentivirus expressing system, and 1.5×106 IFU (inclusion-forming unit) lentiviruses were administered intratracheally to ovalbumin (OVA)-sensitized murine asthmatic models. Our results show that lentivirus-delivered siRNA against IL-5 efficiently inhibited the IL-5 messenger ribonucleic acid (mRNA) expression and significantly attenuated the inflammation in lung tissue. Significant decrease of eosinophils and inflammatory cells were found in peripheral blood, bronchoalveolar lavage fluid (BALF), and lung tissue. In addition, significant inhibition of airway hyperresponsiveness (AHR) was found in the mice treated with siRNA against IL-5. These observations demonstrate that siRNA delivered by means of the lentivirus system is possibly an efficacious therapeutic approach for asthma.

关键词： Interleukin-5 (IL-5) Small interfering RNA (siRNA) Airway hyperresponsiveness (AHR) Allergy Lentivirus

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Chinese Medical Journal 2013年第13期126卷 2517-2522页

作者： ZANG Lei DU Peng HAI Yong SU Qing-jun LU Shi-bao liu Tie Department of Orthopedics Beijing Chaoyang Hospital CapitalMedical University Beijing 100020 China (Zang L Du P Hai Y SuQ J Lu SB and Liu T)

Background Coflex, a type of interspinous process implant, can provide intervertebral dynamic stability for surgical segments and effectively relieve lumbocrural pain. However, few studies have described therapeutic strategies and the avoidance of Coflex implant complications. Methods Coflex implant complications in this study included intraoperative or postoperative spinous process fracture, aggravated postoperative lumbocrural pain, dislodgment and malposition. The complications were analyzed, and therapeutic strategies were applied according to the specific complication. The Visual Analogue Scale and Oswestry Disability Index scores were evaluated by using the paired-samples test from SPSS 12.0. Results Conservative treatment was provided to seven patients who experienced aggravated lumbocrural pain even though their devices remained in the correct position, and pedicle screw treatment was used as an alternative in four cases. The Visual Analogue Scale and Oswestry Disability Index scores showed evident improvement in these patients. The Visual Analogue Scale and Oswestry Disability Index scores of two patients who underwent revision were also improved. Conclusions Coflex implants should be avoided in patients with osteoporosis, a narrow interspinous space and intervertebral coronal spondylolysis, or sagittal instability. Furthermore the device choice, depth of implantation, and clamping intensity should be appropriate. Conservative treatment can be provided to patients with symptoms if the device remains in the correct position; however, revisions and salvages should be undertaken with internal fixation of pedicle screws for patients with device malposition, intraoperative implantation failure, or device intolerance.

关键词： lumbar spine non-fusion, dynamic stabilization system, coflex complication

Characterization of Nanocrystallizatin Surface Layer of 0.4C-1Cr Low Alloy Steel Prepared by Ultrasonic Particulate Peening

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材料热处理学报 2004年第05B期25卷 1257-1259页

作者： ZHANGjun-bao liuYu-liang ZHAOXin-qi WUJie SONGHong-wei XIONGTian-ying baosteelTechnologyCenter BaoshanIron＆SteelCO.LTD.ShanghaiChina InstituteofMetalResearch ChineseAcademyofSciencesShenyangChina

A nanostructured surface layer was fabricated in a quenched and tempered 0.4C-lCr low alloy steel by ultrasonic particulate peening technique. The microstructure of the nanocrystalline surface layer was characterized by means of TEM and Mossbauer spectroscopy. Experimental results reveal that both cementite and ferrite nanocrystals with an average size of 5 nm were formed in the surface layer of the steel, phase transformation of austenite and dissolution of cementite maybe occur in the process of ultrasonic paniculate peening.

关键词：显微结构超声波喷丸处理表面毫微结晶 0.4C-1Cr低合金钢

Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang Han Jia Tuo liu Yuzhen Yang jun Yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie liu Changqing Xu Da-Jian Wu Ying Cheng Xiao-jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

4H-SiC基半超结VDMOSFET单粒子效应加固研究

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电力电子技术 2017年第9期51卷 64-67页

作者：刘忠永蔡理刘保军刘小强空军工程大学理学院陕西西安710051 空军第一航空学院河南信阳464000

研究了"高K栅"介质HfO_2和电荷失配对4H-碳化硅(SiC)基半超结垂直双扩散金属氧化物半导体场效应晶体管(VDMOSFET)单粒子烧毁(SEB)和单粒子栅穿(SEGR)效应的影响,并给出了一种加固结构。研究结果表明,HfO_2介质的应用对器件SEB效应没有影... 详细信息

研究了"高K栅"介质HfO_2和电荷失配对4H-碳化硅(SiC)基半超结垂直双扩散金属氧化物半导体场效应晶体管(VDMOSFET)单粒子烧毁(SEB)和单粒子栅穿(SEGR)效应的影响,并给出了一种加固结构。研究结果表明,HfO_2介质的应用对器件SEB效应没有影响,但栅氧化层电场峰值降低了83%,对SEGR效应有加固作用。结合HfO_2介质层和增加沟道掺杂浓度两种方法的加固结构,在不影响器件阈值电压的同时,器件的SEB闽值电压为1 290 V,提高了28%;栅氧化层的电场峰值为2.2×10~6V/cm,降低了80%。当N柱区掺杂浓度大于P柱区时,器件的抗SEB能力有所增强,但N柱区掺杂浓度小于P柱区时,器件的抗SEB能力减弱。

关键词：垂直双扩散金属氧化物半导体效应管单粒子效应

Numerical Simulation Study on the Surface Deflection of Cylindrical Shallow Shell

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武汉理工大学学报 2006年第S2期28卷 577-581页

作者： XING Zhongwen~1 bao jun~1 liu Zhongyuan~1 YANG Yuying~2 SUN Zhenzhong~2 1.School of Mechanical and Electrical Engineering,Harbin Institute of Technology,Harbin 150001,China 2.School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China School of Mechanical and Electrical Engineering Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The increasing applications of new materials such as high strength low alloy (HSAL) steels and aluminum alloy sheets have lead to greater focus on the surface deflections of auto body panels in the automobile industry in recent *** finite element models of cylindrical shallow shell that can represent auto body panels are *** simulations of forming and unloading of cylindrical shallow shell are carried *** a measurement and evaluation method of the surface deflection is *** simulations of surface deflections with various blank homing forces (BHF) show great agreement with the experi- mental *** influence laws of sheet thickness and material properties such as yield strengthσs,strain-hardening exponent n,anisotropy parameter r and strength coefficient k on the surface deflection are achieved by simulations,which give a basic refer- ence for controlling surface deflections.

关键词： cylindrical shallow shell surface deflection numerical simulation material properties

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling liu Biao Meng Tao Chen Yu Han jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy